Techniques for dyeing cloth, leather, etc. by ink jet method has been known in the art. Advantages of dyeing by ink jet method include excellent productivity and readiness with which design change requirements can be met.
On the other hand, printing by ink jet method could result in uneven dyeing because ink jet method, which achieves dyeing with aggregates of shot ink dots, were susceptible to the surface configuration of and the thickness variation in media to be dyed such as cloth and leather.
JP 2000-45188 A, for example, proposes natural or synthetic leather capable of reducing occurrence of dye unevenness in ink jet printing. In order to suppress the occurrence of dye unevenness, the leather therein proposed is previously provided on its surface with a penetration adjusting layer and a color development adjusting layer, the penetration adjusting layer containing a water repellent and a binder resin, the color development adjusting layer containing a cationic substance and a binder resin. These layers are formed by spray dry method, coating method, or the like.